Application of Robust Model Predictive Control to a Renewable Hydrogen-based Microgrid

In order to cope with uncertainties present in the renewable energy generation, as well as in the demand consumer, we propose in this paper the formulation and comparison of three robust model predictive control techniques, i. i. e., multi-scenario, tree-based, and chance-constrained model predictive control, which are applied to a nonlinear plant-replacement model that corresponds to a real laboratory-scale plant located in the facilities of the University of Seville. Results show the effectiveness of these three techniques considering the stochastic nature, proper of these systems

A resilient approach for distributed MPC-based economic dispatch in interconnected microgrids

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Economic dispatch of interconnected microgrids that is based on distributed model predictive control (DMPC) requires the cooperation of all agents (microgrids). This paper discusses the case in which some of the agents might not comply with the decisions computed by performing a DMPC algorithm. In this regard, these agents could obtain a better performance at the cost of degrading the performance of the network as a whole. A resilient distributed method that can deal with such issues is proposed and studied in this paper. The method consists of two parts. The first part is to ensure that the decisions obtained from the algorithm are robustly feasible against most of the attacks with high confidence. In this part, we employ a two-step randomization-based approach to obtain a feasible solution with a predefined level of confidence. The second part consists in the identification and mitigation of the adversarial agents, which utilizes hypothesis testing with Bayesian inference and requires each agent to solve a mixed-integer problem to decide the connections with its neighbors. In addition, an analysis of the decisions computed using the stochastic approach and the outcome of the identification and mitigation method is provided. The performance of the proposed approach is also shown through numerical simulations.Peer ReviewedPostprint (author's final draft

Non-centralized Control for Flow-based Distribution Networks: A Game-theoretical Insight

This paper solves a data-driven control problem for a flow-based distribution network with two objectives: a resource allocation and a fair distribution of costs. These objectives represent both cooperation and competition directions. It is proposed a solution that combines either a centralized or distributed cooperative game approach using the Shapley value to determine a proper partitioning of the system and a fair communication cost distribution. On the other hand, a decentralized noncooperative game approach computing the Nash equilibrium is used to achieve the control objective of the resource allocation under a non-complete information topology. Furthermore, an invariant-set property is presented and the closed-loop system stability is analyzed for the non cooperative game approach. Another contribution regarding the cooperative game approach is an alternative way to compute the Shapley value for the proposed specific characteristic function. Unlike the classical cooperative-games approach, which has a limited application due to the combinatorial explosion issues, the alternative method allows calculating the Shapley value in polynomial time and hence can be applied to large-scale problems.Generalitat de Catalunya FI 2014Ministerio de Ciencia y Educación DPI2016-76493-C3-3-RMinisterio de Ciencia y Educación DPI2008-05818Proyecto europeo FP7-ICT DYMASO

Chance-constrained model predictive control applied to inventory management in hospitalary pharmacy

Trabajo presentado a la 2nd KES International Conference on Innovation in Medicine and Healthcare (InMed-14), celebrada en San Sebastian (España) del 9 al 11 de julio de 2014.This extended abstract addresses the preliminary results of applying uncertainty handling strategies and advanced control techniques to the inventary management of hospitality pharmacy. Inventory management is one of the main tasks that a pharmacy department has to carry out in a hospital. It is a complex problem because it requires to establish a tradeoff between contradictory optimization criteria. The final goal of the proposed research is to update the inventory management system of hospitals such that it is possible to reduce the average inventory while maintaining preestablished clinical guarantees.The authors would like to acknowledge Junta de Andalucía (Pharmacontrol Project, P12- TIC-2400), for funding this work.Peer Reviewe

The role of platform quality and publicly owned platforms in the free-to-air broadcasting industry

In this study, we consider the role of a publicly owned platform and programme quality in the free-to-air broadcasting industry. We compare the equilibrium levels of advertising under private and mixed duopoly competition, and show that the connection between programme quality and advertising incentives is drastically different in each scenario. We also consider the welfare implications of our analysis and generate policy implications regarding the optimal level of government intervention in the broadcasting industry

On the Comparison of Stochastic Model Predictive Control Strategies Applied to a Hydrogen-based Microgrid

In this paper, a performance comparison among three well-known stochastic model predictive control approaches, namely, multi-scenario, tree-based, and chance-constrained model predictive control is presented. To this end, three predictive controllers have been designed and implemented in a real renewable-hydrogen-based microgrid. The experimental set-up includes a PEM electrolyzer, lead-acid batteries, and a PEM fuel cell as main equipment. The real experimental results show significant differences from the plant components, mainly in terms of use of energy, for each implemented technique. Effectiveness, performance, advantages, and disadvantages of these techniques are extensively discussed and analyzed to give some valid criteria when selecting an appropriate stochastic predictive controller.Ministerio de Economía y Competitividad DPI2013-46912-C2-1-RMinisterio de Economía y Competitividad DPI2013-482443-C2-1-

Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach

In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-

Life adapted to precariousness: The ecology of drylands

Drylands occupy approximately 40 % of the Earth's surface. Their peculiar hydrological regime, with water as the main limiting factor, together with other characteristics, such as the variability of rainfall and their ecological heterogeneity, turn these regions into one of the main and most relevant sets of biomes on the planet. Beyond their stereotypical conception as places with a low economic and ecological profile, these territories have enormous biodiversity and support 40 % of the world's population. Global warming is increasing atmospheric aridity and the strategies developed over millennia by their inhabitants are a model to learn from. Preserving these places is essential to combat climate change, and to do so, it is essential to have an in-depth understanding of their structure and functioning.This work was funded by the European Research Council (Grant Agreement Nº 647038, BIODESERT) and the Valencian Regional Government (CIDEGENT/2018/041). Emilio Guirado receives funding from the Regional Department of Education, Culture, and Sport of the Valencian Regional Government and the European Social Fund [project APOSTD/2021/188]

A comprehensive model of adjustment to pain in the co-occurrence of PTSD and chronic musculoskeletal pain: vulnerability and protective pathways

There are a significant comorbidity between PTSD and chronic pain. Thus, studies clarifying the vulnerability and protective variables and mechanisms associated with PTSD and chronic pain are needed. The aim of this study was to examine the association between trauma, resilience, PTSD symptoms, and the variables included in the fear-avoidance models (anxiety sensitivity, catastrophizing, fear-avoidance beliefs, fear of pain, pain hypervigilance) as well as pain acceptance and experiential avoidance in explaining adjustment to chronic pain (pain intensity, pain-related disability and emotional distress). Method: the sample consisted of 229 patients with chronic musculoskeletal back pain. Results: Structural Equation Modelling was used. Statistical tests indicated that the hypothesized model adequately fitted the data (RMSEA = .07; CFI = .99; NNFI = .98; TLI = .96). The χ2 test was significant (χ2 (8) = 19.25, χ2 /dl = 2.40, p = .014). The results provided support for the hypothesized model. All the standardized path coefficients were significant (p < .05). Conclusions: This study provides empirical support for the potential role of PTSD symptoms in fear-avoidance models of chronic pain, and may provide support for the diathesis-stress model of pain. It is the first comprehensive model of adjustment to pain to consider vulnerability and protective adaptation mechanisms in patients who have undergone a traumatic event. The study highlights the importance of a comprehensive framework of reference to understand the comorbidity of PTSD and chronic musculoskeletal pain, and the need to provide well-designed treatment programs for the simultaneous treatment of these conditions.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Desertifying deserts

The current definition of desertification excludes hyper-arid zones given their lack of economic activity. However, the 101 million people living there, ongoing land degradation associated with the use of groundwater for intensive agriculture and climate-change-induced aridity call for a revision of this definition.This work was funded by the European Research Council grant agreement no. 647038 (BIODESERT). F.T.M. acknowledges support from Generalitat Valenciana (CIDEGENT/2018/041)